Techniques for implementing dynamic volume adjustment by a virtual assistant are provided. In one embodiment, the virtual assistant can receive a voice query or command from a user, recognize the content of the voice query or command, process the voice query or command based on the recognized content, and determine an auditory response to be output to the user. The virtual assistant can then identify a plurality of criteria for automatically determining an output volume level for the response, where the plurality of criteria including content-based criteria and environment-based criteria, calculate values for the plurality of criteria, and combine the values to determine the output volume level. The virtual assistant can subsequently cause the auditory response to be output to the user at the determined output volume level.